diff --git a/include/llvm/MC/MCObjectStreamer.h b/include/llvm/MC/MCObjectStreamer.h
index 7d76ab172bd..a69075ddd00 100644
--- a/include/llvm/MC/MCObjectStreamer.h
+++ b/include/llvm/MC/MCObjectStreamer.h
@@ -72,7 +72,7 @@ public:
   virtual void ChangeSection(const MCSection *Section);
   virtual void EmitInstruction(const MCInst &Inst);
   virtual void EmitInstToFragment(const MCInst &Inst);
-  virtual void EmitValueToOffset(const MCExpr *Offset, unsigned char Value);
+  virtual bool EmitValueToOffset(const MCExpr *Offset, unsigned char Value);
   virtual void EmitDwarfAdvanceLineAddr(int64_t LineDelta,
                                         const MCSymbol *LastLabel,
                                         const MCSymbol *Label,
diff --git a/include/llvm/MC/MCStreamer.h b/include/llvm/MC/MCStreamer.h
index 31fb6d4bdc5..c141dfbc96e 100644
--- a/include/llvm/MC/MCStreamer.h
+++ b/include/llvm/MC/MCStreamer.h
@@ -503,7 +503,8 @@ namespace llvm {
     /// @param Offset - The offset to reach. This may be an expression, but the
     /// expression must be associated with the current section.
     /// @param Value - The value to use when filling bytes.
-    virtual void EmitValueToOffset(const MCExpr *Offset,
+    /// @return false on success, true if the offset was invalid.
+    virtual bool EmitValueToOffset(const MCExpr *Offset,
                                    unsigned char Value = 0) = 0;
 
     /// @}
diff --git a/lib/MC/MCAsmStreamer.cpp b/lib/MC/MCAsmStreamer.cpp
index a2fb7a40d43..afad5d530cf 100644
--- a/lib/MC/MCAsmStreamer.cpp
+++ b/lib/MC/MCAsmStreamer.cpp
@@ -199,7 +199,7 @@ public:
   virtual void EmitCodeAlignment(unsigned ByteAlignment,
                                  unsigned MaxBytesToEmit = 0);
 
-  virtual void EmitValueToOffset(const MCExpr *Offset,
+  virtual bool EmitValueToOffset(const MCExpr *Offset,
                                  unsigned char Value = 0);
 
   virtual void EmitFileDirective(StringRef Filename);
@@ -744,11 +744,12 @@ void MCAsmStreamer::EmitCodeAlignment(unsigned ByteAlignment,
                        1, MaxBytesToEmit);
 }
 
-void MCAsmStreamer::EmitValueToOffset(const MCExpr *Offset,
+bool MCAsmStreamer::EmitValueToOffset(const MCExpr *Offset,
                                       unsigned char Value) {
   // FIXME: Verify that Offset is associated with the current section.
   OS << ".org " << *Offset << ", " << (unsigned) Value;
   EmitEOL();
+  return false;
 }
 
 
diff --git a/lib/MC/MCNullStreamer.cpp b/lib/MC/MCNullStreamer.cpp
index 432974f8d77..ba7f81f722f 100644
--- a/lib/MC/MCNullStreamer.cpp
+++ b/lib/MC/MCNullStreamer.cpp
@@ -80,8 +80,8 @@ namespace {
     virtual void EmitCodeAlignment(unsigned ByteAlignment,
                                    unsigned MaxBytesToEmit = 0) {}
 
-    virtual void EmitValueToOffset(const MCExpr *Offset,
-                                   unsigned char Value = 0) {}
+    virtual bool EmitValueToOffset(const MCExpr *Offset,
+                                   unsigned char Value = 0) { return false; }
     
     virtual void EmitFileDirective(StringRef Filename) {}
     virtual bool EmitDwarfFileDirective(unsigned FileNo, StringRef Directory,
diff --git a/lib/MC/MCObjectStreamer.cpp b/lib/MC/MCObjectStreamer.cpp
index d8f18268aab..f2911fa07b9 100644
--- a/lib/MC/MCObjectStreamer.cpp
+++ b/lib/MC/MCObjectStreamer.cpp
@@ -232,12 +232,12 @@ void MCObjectStreamer::EmitDwarfAdvanceFrameAddr(const MCSymbol *LastLabel,
   new MCDwarfCallFrameFragment(*AddrDelta, getCurrentSectionData());
 }
 
-void MCObjectStreamer::EmitValueToOffset(const MCExpr *Offset,
+bool MCObjectStreamer::EmitValueToOffset(const MCExpr *Offset,
                                          unsigned char Value) {
   int64_t Res;
   if (Offset->EvaluateAsAbsolute(Res, getAssembler())) {
     new MCOrgFragment(*Offset, Value, getCurrentSectionData());
-    return;
+    return false;
   }
 
   MCSymbol *CurrentPos = getContext().CreateTempSymbol();
@@ -249,8 +249,9 @@ void MCObjectStreamer::EmitValueToOffset(const MCExpr *Offset,
     MCBinaryExpr::Create(MCBinaryExpr::Sub, Offset, Ref, getContext());
 
   if (!Delta->EvaluateAsAbsolute(Res, getAssembler()))
-    report_fatal_error("expected assembly-time absolute expression");
+    return true;
   EmitFill(Res, Value, 0);
+  return false;
 }
 
 // Associate GPRel32 fixup with data and resize data area
diff --git a/lib/MC/MCParser/AsmParser.cpp b/lib/MC/MCParser/AsmParser.cpp
index 64d0dd8563c..1af7cd9ee0d 100644
--- a/lib/MC/MCParser/AsmParser.cpp
+++ b/lib/MC/MCParser/AsmParser.cpp
@@ -1970,6 +1970,7 @@ bool AsmParser::ParseDirectiveOrg() {
   CheckForValidSection();
 
   const MCExpr *Offset;
+  SMLoc Loc = getTok().getLoc();
   if (ParseExpression(Offset))
     return true;
 
@@ -1989,9 +1990,11 @@ bool AsmParser::ParseDirectiveOrg() {
 
   Lex();
 
-  // FIXME: Only limited forms of relocatable expressions are accepted here, it
-  // has to be relative to the current section.
-  getStreamer().EmitValueToOffset(Offset, FillExpr);
+  // Only limited forms of relocatable expressions are accepted here, it
+  // has to be relative to the current section. The streamer will return
+  // 'true' if the expression wasn't evaluatable.
+  if (getStreamer().EmitValueToOffset(Offset, FillExpr))
+    return Error(Loc, "expected assembly-time absolute expression");
 
   return false;
 }
diff --git a/lib/MC/MCPureStreamer.cpp b/lib/MC/MCPureStreamer.cpp
index 8a3bf8778f9..a770c974380 100644
--- a/lib/MC/MCPureStreamer.cpp
+++ b/lib/MC/MCPureStreamer.cpp
@@ -46,7 +46,7 @@ public:
                                     unsigned MaxBytesToEmit = 0);
   virtual void EmitCodeAlignment(unsigned ByteAlignment,
                                  unsigned MaxBytesToEmit = 0);
-  virtual void EmitValueToOffset(const MCExpr *Offset,
+  virtual bool EmitValueToOffset(const MCExpr *Offset,
                                  unsigned char Value = 0);
   virtual void FinishImpl();
 
@@ -184,9 +184,10 @@ void MCPureStreamer::EmitCodeAlignment(unsigned ByteAlignment,
     getCurrentSectionData()->setAlignment(ByteAlignment);
 }
 
-void MCPureStreamer::EmitValueToOffset(const MCExpr *Offset,
+bool MCPureStreamer::EmitValueToOffset(const MCExpr *Offset,
                                        unsigned char Value) {
   new MCOrgFragment(*Offset, Value, getCurrentSectionData());
+  return false;
 }
 
 void MCPureStreamer::EmitInstToFragment(const MCInst &Inst) {
diff --git a/lib/Target/PTX/PTXMCAsmStreamer.cpp b/lib/Target/PTX/PTXMCAsmStreamer.cpp
index 270ed2d29fd..38ecf5240a8 100644
--- a/lib/Target/PTX/PTXMCAsmStreamer.cpp
+++ b/lib/Target/PTX/PTXMCAsmStreamer.cpp
@@ -162,7 +162,7 @@ public:
   virtual void EmitCodeAlignment(unsigned ByteAlignment,
                                  unsigned MaxBytesToEmit = 0);
 
-  virtual void EmitValueToOffset(const MCExpr *Offset,
+  virtual bool EmitValueToOffset(const MCExpr *Offset,
                                  unsigned char Value = 0);
 
   virtual void EmitFileDirective(StringRef Filename);
@@ -478,8 +478,8 @@ void PTXMCAsmStreamer::EmitValueToAlignment(unsigned ByteAlignment,
 void PTXMCAsmStreamer::EmitCodeAlignment(unsigned ByteAlignment,
                                          unsigned MaxBytesToEmit) {}
 
-void PTXMCAsmStreamer::EmitValueToOffset(const MCExpr *Offset,
-                                         unsigned char Value) {}
+bool PTXMCAsmStreamer::EmitValueToOffset(const MCExpr *Offset,
+                                         unsigned char Value) {return false;}
 
 
 void PTXMCAsmStreamer::EmitFileDirective(StringRef Filename) {
diff --git a/tools/lto/LTOModule.cpp b/tools/lto/LTOModule.cpp
index 2b89e6240c9..af5a0a66f51 100644
--- a/tools/lto/LTOModule.cpp
+++ b/tools/lto/LTOModule.cpp
@@ -589,8 +589,8 @@ namespace {
                                       unsigned MaxBytesToEmit) {}
     virtual void EmitCodeAlignment(unsigned ByteAlignment,
                                    unsigned MaxBytesToEmit) {}
-    virtual void EmitValueToOffset(const MCExpr *Offset,
-                                   unsigned char Value ) {}
+    virtual bool EmitValueToOffset(const MCExpr *Offset,
+                                   unsigned char Value ) { return false; }
     virtual void EmitFileDirective(StringRef Filename) {}
     virtual void EmitDwarfAdvanceLineAddr(int64_t LineDelta,
                                           const MCSymbol *LastLabel,